Amalgamator for the recovery of gold



A. J. CLARK El AL Dec. 29, 1936.

AMALGAMRTOR FOR-THE RECOVERY "OF GOLD 4 Sheets-Sheet 1 Filed March 28, l935 3nventors #220121 116%, A Warrenfif 1 0 165 (Ittorne Dec. 29, 1936. A, L K ET AL 2,065,967

AMALGAMATOR FOR THE RECOVERY OF GOLD Filed March 28, 1935 4 Sheets-Sheet 2 Summon? fllhn/ (I CZQJ'ZI Bu aw Warren/E Todd ml Q W ultorllcg Deb. 29, 1936. -A. J.CLARK ET AL AMLGAMATOR FOR THE RECOVERY OF GOLD Filed March 2a, 1935 4 Sheets-Sheet 3 4 a w 0 u: 1 a z 5 2 m" u Z "M M a 1 N. 4/ 0 m V 4 n 0. 3 3 7 4 a z Zhwentors (I Clark Todd (Ittomegs Deal 29, 1936. A'. J. CLARK ET AL 06 AMALGAMATOR FOR THE RECOVERY" OF aogg' 4 sheets-sheet 4 Filed March 28, 1935 249 27 E J: 311mg; Warren/Z 25M (Ittorneg Patented Dec. 29, 1936 PATENT OFFICE AMALGAMATOR FOR OF GOLD THE RECOVERY Allan J. Clark and Warren H. Todd, Lead, S. Dak.

Application March 28, 1935, Serial No. 13,523

2 Claims.

The present invention relates to improvements in amalgamators for the recovery of gold and resides in certain improvements over our prior Patent 1,894,159 granted January 10, 1933.

In common with the objects and purposes of the prior device illustrated and described in our patent aforesaid, the present invention aims further to increase the yield by providing a construction which will require that the course of flow of the pulp be changed at right angles a greater number of times thus further inducing precipitation and amalgamation.

A further object of the invention is to provide in addition to the dilution water a backwash, discharged at higher pressure through several nozzles directed against the stream as it starts its vflow from the first box whereby to check the speed of flow and afford opportunity for the settling out of the heavy amalgam.

q line 44 in Figure 2.

Figure 5 is a similar view takenon the line 55 also in Figure 2.

Figure 6 is a vertical section taken on the line 6-5 in Figure 2.

Figure 7 is a side elevation of the apparatus, and

Figure 8 is a top plan view with the covers removed.

Referring more particularly to the drawings, l i represents the discharge from a rod mill or the like whereby the thick pulp which is a mixture of ground ore particles with water, to which mercury has been added, is caused to discharge into the improved amalgamator. Such thick pulp is directed by the discharge II on to a screen or perforated plate I2. This screen [2 may be supported in any desired manner, preferably for ready removal, as upon the upper edges of the walls of the tray l3. The tray l3 rests removably in the pulp box or first launder M. A horizontal delivery pipe l5 for dilution water is placed at one end of the pulp box M and below the screen l2 therein, this pipe having a slot I6 directed substantially horizontally into the tray Hi. This delivery pipe is connected to a supply pipe H to introduce a supply of water.

At the other end of the tray l3 and facing the distributing pipe i5 is a pressure distributing pipe if! having a number of nozzles l9 connected therewith and projecting substantially horizontally into the tray l3 and directed opposite to the flow of water out through the slot Hi. The pressure distributing pipe 18 is connected by a supply pipe 2!) with a source of water or other fluid under higher pressure than the pipe ll; or these pipes may be connected both to the city or other water supply, in which case the pipe i7 will be made of greater diameter than the pipe 26 thus causing higher pressure in the distributing pipe I8 and nozzles 89.

As shown in Figures 1 and 5, the tray 83, which is an amalgam tray, is provided with a lip or weir 2| at one end thereof which projects through a cut-away portion 22 in the adjacent end wall of the pulp box Hi and extends also through the cut-away portion 23 of the adjacent wall of an amalgam tray 24 disposed in the second launder 25. This second launder is disposed at an inclination as shown in Figure 6.from a high point at its receiving end down to a low point at its discharging end where its inner side wall is formed with a weir or lip structure 48 extending through a cut-away portion 4i inlthe inner wall of the second launder. This lip fits over an outturned lip 25 on the inner adjacent wall of an amalgam tray 21 in the third launder 28. The lip 26 is lower than the other walls of thetray 2'5 and forms a weir over which the pulp may overflow into the third launder, which third launder is also inclined as indicated in Figure 4.

The lower end of the tray 27 and its launder 28 discharge into a fourth launder 29 over a weir 30 shown in Figure 4. The fourth launder 29 extends at an inclination down beneath the second launder.

The discharge from the third launder 28 to the fourth launder 29 is through'an opening 43. The openings 22, M and 43 may be all in the same wall M, which wall is common to the first, second, third and fourth launders and forms part of the weir 30 between the third and fourth launders. The

fourth launder may have an amalgam plate 42 therein.

It will be apparent that the first launder is at right angles to the second launder, the second launder at right angles to the third launder and the fourth launder at right angles to the third launder. Accordingly the flow coming in the delivery pipe I l is required to turn at right angles in the first launder M in order to flow over the weir 2|; it is then required a second time to change its course at right angles before flowing down the long expanse of the second launder which is an elongated launder. When arriving at the lower end of the second launder the flow must again change its course at 90 in order to flow into the third launder 28, and a fourth right angle turn is made when the pulp flows over the weir and into the fourth or last launder 29. Thus the course of the flow of the pulp makes four right-angled turns and passes through four.

boxes instead of three. At each right angle turn the rate of flow is checked so that ample time is allowed for precipitation and amalgamation. The arrangement of the four boxes is compact and such as to enable the device to be contained within small compass. This is of value in that the same may be constructed as a unit for removably mounting upon a carriage or stationary frame such that the entire unit, comprising all four boxes, may be lifted off the foundation or carriage and transported to a clean-out room.

The carriage or foundation is shown generally at 3! in Figure 7. Preferably a flat bottom 32 is provided for the entire unit extending beneath all boxes to enable this device to seat readily in the-frame or carriage 3|. Lugs 33 are provided on the unit to receive lifting tackle. It is proposed to lift the whole device with a crane and to convey it to a guarded clean-up room before it is unlocked. Over the various launders are protective screens secured in place by padlocks or other means 44 which may be removed after the device is in the guarded clean-up room.

,In Figure 8 removable rifiles 34 and 35 are shown in certain of the boxes. In applying the invention to a larger mill it was necessary to enlarge the compartments in proportion to the tonnage. In so doing even distribution of pulp in these wider boxes was diflicult and was finally accomplished by placing removable riffles 34 and 35 in two of them, as shown in this Figure 8. It is not necessary to attach the rifiies to the boxes and their height may be varied to control the rate of flow. These rifiles will also settle out some amalgam.

The dilution water comes in through the pipe l5 which introduces a flow of water in the direction of flow of the pulpthrough the device. Thus the rate of flow of pulp tends to be increased by the introduction of the dilution water.

To check this, backwash water through the pipe l8 and nozzles I9 is introduced at a higher pressure in order to offset any increase in flow rate. The backwash is in direct opposition to the movement of the pulp out of the first launder into the second launder and afiords opportunity for settling out of the heavy amalgam even in the first launder. High pressures are not necessary in the backwash but some pressure is desirable to effect a quick momentary checking of the flow. The chip basket in the discharge end of the grinding mill, as employed in our prior patent, has been replaced by the single screen l2 or perforated plate, which covers the whole of the first compartment.

The compact arrangement of the device is facilitated by arranging the second and third launders in parallelism, with the first and fourth in parallelism with one another, the first and fourth partially overlapping and the fourth extending beneath the sloping bottom of the long second launder.

It will be understood that the various launders contain, or may contain, removable trays, or containers of copper or other amalgamable metal. These trays may be of any desirable depth.

It will be obvious that various changes may be made in the construction, combination and arrangement of parts which could be used without departing from the spirit of our invention and we do not mean to limit'the invention to such details except as particularly pointed out in the claims.

Having thus described our invention what We claim and desire to secure by Letters Patent of the United States is:

. 1. In an apparatus for the recovery of gold, a plurality of launders arranged angularly in sequence to receive the pulp, means for introducing the pulp to the launder first in series, a slotted pipe at one end of the launder in connection with a source of water supply for introducing dilution water in a direction the same as that of the pulp flow to the second launder, and a high pressure pipe having a plurality of nozzles opposed to the slot and in communication with a source of higher pressure water for checking the rate 01' the flow of the pulp to the second launder.

2. In an apparatus for the recovery of gold, a plurality of launders arranged angularly in sequence to receive the pulp, means for introducing the pulp to the launder first in series, means for supplying dilution water to the first launder in the direction of flow of pulp to the second launder, and means opposed to said water supplying means for introducing water under pressure to said first launder in a direction opposed to the fiow of said pulp and dilution water to check the rate of flow of pulp to the second launder.

ALLAN J. CLARK. WARREN H. TODD. 

